Optical disc, a recorder, a player, a recording method, and a reproducing method that are all used for the optical disc

ABSTRACT

A video object is recorded on an optical disc. The video object is composed of at least one video object unit, and each video object unit contains control information and video data and has a presentation time of one second or shorter. The control information relates to display control and copying control for the video object unit.

This Application is a Divisional application Ser. No. 09/662,312, filedSep. 14, 2000, now U.S. Pat. No. 6,370,321 B1, which is a Divisionalapplication Ser. No. 09/612,264, filed Jul. 7, 2000, Now U.S. Pat. No.6,272,286 B1.

BACKGROUND OF THE INVENTION

(1) Field of the Invention

The present invention relates to an optical disc from and into which aread and a write can be performed and recording and reproducing methodsto record and reproduce data on the optical disc. More specifically, thepresent invention relates to an optical disc on which video data isrecorded, and recording and reproducing methods used for such opticaldisc.

(2) Description of the Related Art

DVD-RAM (Digital Video Disc-Random Access Memory) has been recentlydeveloped in the field of rewritable optical discs. A DVD-RAM is a phasechange optical disc with a several-GB capacity that exceeds theconventional limits of around 650 MB.

DVD-RAMs can be used by computers to store various kinds of data. Inaddition, there are hopes that DVD-RAMs will be used to record AV (audiovideo) data for audio and video. While common conventional recordingdevices such as video type recorders (VTRs) record audio and video ontoa magnetic tape, there are hopes that such recording will be performedby optical disc recorders that use optical discs.

An optical disc recorder/player that can be used in place of a standardVTR receives a TV (television) broadcast, converts (compresses) a TVsignal in the received broadcast into digital AV data, and records thedigital AV data onto a DVD-RAM. When reproducing the AV data, theoptical disc recorder/player reads the AV data from the DVD-RAM,converts the read AV data into an analog AV signal, and outputs it to adisplay unit. The generated AV data conforms to MPEG (Motion PictureExpert Group) prescribed in ISO/IEC 13818 (International StandardizationOrganization/International Electrotechnical Commission).

With some recent analog TV broadcasts, digital data is multiplexed intoa TV signal during a vertical blanking interval (hereafter called “VBI”,with the digital data multiplexed during a VBI being called “VBI data”).In teletext broadcasting, for instance, text data is multiplexed as VBIdata during VBIs.

In a TV (or video) signal conforming to NTSC (National Television SystemCommittee) system, one frame (i.e., two fields) is composed of 525horizontal scanning lines, and VBI data can be multiplexed during aperiod that corresponds to the tenth to twenty-first horizontal scanninglines during a VBI and a period that corresponds to the 273rd to the284th scanning lines during a VBI.

In addition to text data, VBI data can be information such as letterboxcontrol information and copy control information. The letterbox controlinformation is used to control display of an image with an aspect ratioof 4:3 on a display screen with an aspect ratio of 16:9 or 14:9. Thecopy control information shows whether VTRs are permitted to record theimages. A method to multiplex such information as VBI data is defined,for instance, in Journal of the Institute of Television Engineers ofJapan vol. 49 No. 9 (1995), and ETS300 294 (European TelecommunicationsStandards) “Television Systems 625-Line Television Wide ScreenSignaling(WSS)”.

The letterbox control information and the copy control information aremultiplexed into a program or a commercial. As the VBI data can bemultiplexed into each field, it is possible to change, for instance,display and copy protection settings only for a certain commercial bymultiplexing VBI data into the certain commercial. More specifically, itis possible to change an aspect ratio of a display image and/or allowcopying only for commercials by multiplexing appropriate VBI data duringthe commercial periods.

VTRs for S-VHS (Super Video Home System) are capable of recording a TVsignal including VBI data onto a magnetic tape, reproducing the TVsignal, and having the TV signal displayed on a display unit. Thisallows the display unit to recognize the multiplexed VBI data such asletterbox control information and to control the displaying of aletterbox image in synchronization with the TV signal.

However, when a conventional optical disc recorder/player receives theTV broadcast, encodes an analog TV signal in the broadcast intocompressed digital data, and records the compressed data onto an opticaldisc, any VBI data in the TV signal will be lost. As a result, theconventional optical disc recorder/player cannot change the displaystyle or copying permission during fifteen or thirty-second commercialperiods when reproducing AV data from an optical disc.

SUMMARY OF THE INVENTION

The present invention aims to provide an optical disc, an optical discrecorder, an optical disc player, an optical disc recording method, anoptical disc reproducing method that can effectively use VBI datamultiplexed into a video signal.

The above object can be achieved by an optical disc of on which at leastone video object is recorded. Each video object contains at least onevideo object unit, and each video object unit contains controlinformation and video data, and has a presentation time of one second orshorter. The control information relates to at least one of: (a) displaycontrol for the video object unit; and (b) copying control for the videoobject unit.

The above object can be also achieved by an optical disc recorder thatrecords a video object onto a recordable optical disc, including: anextracting unit for extracting data that has been multiplexed into anaudio-video signal, the data relating to at least one of: (a) displaycontrol; and (b) copying control; an encoding unit for encoding theaudio-video signal to generate the video object containing at least onevideo object unit that has a presentation time of one second or shorter;an generating unit for generating, based on the extracted data, controlinformation relating to at least one of: (a) display control for eachvideo object unit in the video object; and (b) copying control for eachvideo object unit in the video object; and a controlling unit for havingthe encoding unit to insert the generated control information into eachvideo object unit.

The above object can be also achieved by an optical disc player thatreproduces a video object recorded on an optical disc, the video objectcontaining at least one video object unit that each has a presentationtime of one second or shorter. The optical disc player includes: areading unit for reading the video object from the optical disc; aseparating unit for separating each video object unit in the read videoobject into video data, audio data, and control information; a decodingunit for decoding the video data and the audio data obtained byseparating the video object unit to generate an audio-video signalcorresponding to the video object unit; and a multiplexing unit formultiplexing additional data into the generated audio-video signalduring vertical blanking intervals based on the control information thathas been obtained by separating the video object unit.

Here, each video object may be generated from an analog video signal,and control information may indicate a content of data that ismultiplexed into vertical blanking intervals in the analog video signal.

Here, the control information may show at least one of: (a) a displayposition for the video object unit; (b) copying management conditionsfor the video object unit; and (c) a source-material type for the videoobject unit.

With this construction, each video object unit contains controlinformation, therefore, display control and copying control can beachieved for each video object unit, which is to say, different displayand copying control can be performed for every second or lower. Thisenables the change of, for instance, a display style or copyingpermission during a certain period, such as a commercial, of a program.

Here, each video object unit may contain one control pack and aplurality of video packs into which video data is placed. The controlpack may be placed at a start of the video object unit and contains thecontrol information.

For this construction, a control pack is located at a start of eachvideo object unit. This simplifies an operation by an optical discrecorder to insert a control pack into each video object unit, and socan reduce the operation load of the optical disc recorder.

Here, the control information may further contain status informationshowing which parts of the control information are valid.

As control information additionally contains status information, itbecomes possible to insert a video object unit having valid informationregarding display and copying control and a video object unit havinginvalid information regarding display and copying control into the samevideo object.

Here, the control information may contain letterbox control informationthat shows a display position of images for the video object unit on ascreen.

For this construction, an optical disc player can perform letterboxcontrol for each video object unit, that is, for every second or lower.

Here, the control information may show an aspect ratio of images for thevideo object unit.

For this construction, an aspect ratio can be set, for each video objectunit, in control information.

Here, the control information may contain subtitle mode informationshowing a display position of subtitles for the video object unit.

This allows an optical disc player to control a display position of asubtitle for each video object unit.

Here, the control information may contain film/camera mode informationthat shows whether a source material of the video object unit wasrecorded either by a television camera or on a movie film.

For this construction, film/camera mode can be set, for each videoobject unit, in control information.

Here, the control information may contain information regarding CopyGeneration Managing System to show whether to permit the video objectunit to be copied onto another recording medium.

With this construction, information regarding Copy Generation ManagementSystem can be set, for each video object unit, in control information.

Here, the control information may contain information regarding AnalogProtection System (APS) to show a type of APS copy protection methodused on an analog video signal based on which the video object unit wasgenerated.

With this construction, information regarding Analog Protection Systemcan be set, for each video object unit, in control information.

Here, the control information may contain source information that showswhether a source material of the video object unit is an analogpre-recorded package medium.

With this construction, source information can be set in controlinformation for each video object unit.

Here, in addition to at least one video object that contains controlinformation, at least one piece of stream information and a video objectthat contains no control information may be recorded on the recordableoptical disc. Each piece of stream information may be associated with atleast one video object, and contain: aspect information that shows anaspect ratio of the at least one video object associated with the pieceof stream information; and an application flag that shows either: (a)that the video object is encoded using the aspect ratio in the aspectinformation; or (b) that the video object is not necessarily encodedusing the aspect ratio in the aspect information, and an aspect ratio incontrol information in each video subject unit is used.

As this stream information is recorded separately from each videoobject, an optical disc player can obtain an aspect ratio in the streaminformation for each video object unit without needing to read the videoobject if an application flag is shown as “00b”. In this way, theoptical disc player can judge whether an aspect ratio of a video objector of each video object unit should be used for the video object, usingthe application flag. In addition, a size of a video object thatcontains no control information can be reduced by the size of thiscontrol information.

The above object can be also achieved by a recording to record a videoobject containing at least one video object unit onto an optical disc,including: an extracting step for extracting data that is multiplexedinto an audio-video signal, the data relating to display control andcopying control; an encoding step for encoding the audio-video signal togenerate video data and audio data; a generating step for generatingcontrol information that relates to display control and copying controlbased on the extracted data; and a multiplexing step for multiplexingthe control information, the video data, and the audio data that havebeen generated pinto a video object unit having a presentation time ofone second or shorter.

The above object can be also achieved by a reproducing method toreproduce a video object recorded on an optical disc, including: areading step for reading the video object from the optical disc, thevideo object containing at least one video object unit that each has apresentation time of one second or shorter; a separating step forseparating each video object unit in the read video object into videodata, audio data, and control information; a decoding step for decodingthe video data and the audio data obtained by separating the videoobject unit to generate an audio-video signal corresponding to the videoobject unit; and a multiplexing step for multiplexing additional datainto the generated audio-video signal during vertical blanking intervalsbased on the control information that has been obtained by separatingthe video object unit.

The above object can be also achieved by a program that is recorded on acomputer-readable recording medium and that has a computer perform arecording operation to record a video object containing at least onevideo object unit onto an optical disc. The recording operationincludes: an extracting step for extracting data that is multiplexedinto an audio-video signal, the data relating to display control andcopying control; an encoding step for encoding the audio-video signal togenerate video data and audio data; a generating step for generatingcontrol information that relates to display control and copying controlbased on the extracted data; and a multiplexing step for multiplexingthe control information, the video data, and the audio data that havebeen generated into a video object unit having a presentation time ofone second or shorter.

The above object can be also achieved by a program that is recorded on acomputer-readable recording medium and that has a computer perform areproducing operation to reproduce a video object recorded on an opticaldisc. The reproducing operation includes: a reading step for reading thevideo object from the optical disc, the video object containing at leastone video object unit that each has a presentation time of one second orshorter; a separating step for separating each video object unit in theread video object into video data, audio data, and control information;a decoding step for decoding the video data and the audio data obtainedby separating the video object unit to generate an audio-video signalcorresponding to the video object unit; and a multiplexing step formultiplexing additional data into the generated audio-video signalduring vertical blanking intervals based on the control information thathas been obtained by separating the video object unit.

BRIEF DESCRIPTION OF THE DRAWINGS

These and the other objects, advantages and features of the inventionwill become apparent from the following description thereof taken inconjunction with the accompanying drawings which illustrate a specificembodiment of the invention.

In the drawings:

FIG. 1 shows an external view of an optical disc recorder/player, atelevision set, and a remote controller;

FIG. 2 shows a lead-in area, a data area, a lead-out area within aregion of the optical disc, and a construction of files stored in thedata area;

FIG. 3 shows a data construction of a VR_MOVIE.VRO file;

FIG. 4 shows a data construction of a control pack;

FIG. 5 shows a detailed bit configuration of display control information(DCI) in a control pack;

FIG. 6 shows a relationship between a screen size and a display imagesize;

FIG. 7 shows a detailed bit configuration of copy control information(CCI) in a control pack;

FIG. 8 shows a bit configuration of DCI CCI Status Information;

FIG. 9A shows a data construction of a VR_MANGR.IFO file shown in FIG. 2at different levels;

FIG. 9B shows a bit configuration of a Video Attribute (V_ATR);

FIG. 9C shows an M_VOB_STIN (Movie_VOB_Stream Information Number)contained in M_AVFI (Movie_AV File Information;

FIG. 10 is a block diagram showing a detailed construction of an opticaldisc recorder/player in FIG. 1;

FIG. 11 is a block diagram showing a detailed construction of a VBIDdemodulator;

FIG. 12 is a flowchart showing the processing by the DCI generating unitto generate DCI;

FIG. 13 shows a conversion table for an aspect ratio of an NTSC(National Television System Committee) signal;

FIG. 14 shows a conversion table for an aspect ratio of a PALplus (PhaseAlternation by Line) signal;

FIG. 15 shows a conversion table for Subtitling Mode;

FIG. 16 shows a conversion table for Film/Camera Mode;

FIG. 17 is a flowchart showing the detailed processing by the CCIgenerating unit;

FIG. 18 shows a conversion table for CGMS (Copy Generation ManagingSystem);

FIG. 19 shows a conversion table for APSTB (Analog Protection SystemTrigger Bits);

FIG. 20 shows a conversion table for Source Information;

FIG. 21 is a block diagram showing a detailed construction of a DVDrecorder;

FIG. 22 is a block diagram showing a detailed construction of anencoding unit;

FIG. 23 is a block diagram showing a detailed construction of a systemencoder;

FIG. 24 is a flowchart showing the processing by a system controllingunit to control the encoding; and

FIG. 25 is a block diagram showing a detailed construction of a decodingunit.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following defines technological terms used in this specification.

(i) Video Object (VOB)

A video object (VOB) is stream data generated as a result of a real-timerecording being performed once, and complies with a program streamprescribed in ISO/IEC 13181-1 “Information Technology—Generic Coding ofMoving Pictures and Associated Audio Information: Systems”. The VOBconsists of at least one video object unit (VOBU) that is composed ofvideo data and audio data. For the present invention, a VOBUadditionally contains display control information and copy controlinformation.

(ii) Video Object Unit (VOBU)

A VOBU is composed of at least one GOP (group of pictures), andcontained in a VOB. Each VOBU has a reproduction time of 0.4 to 1.0second although a VOBU at the end of a VOB may have a reproduction timeshorter than 0.4 second, depending on when the recording stops. A VOBUis a pack sequence consisting of packs arranged in a recording order. Apack at a start of a VOBU is either a Video Pack or a Control Pack, andhas a system header. When one VOBU in a VOB starts with a Control Pack,every VOBU in that VOB includes a Control Pack. When one VOBU in a VOBstarts with a Video Pack, no VOBUs in that VOB include a Control Pack.

(iii) Group of Pictures (GOP)

A GOP is defined in ISO/IEC 13818-2 for the MPEG standard, and refers topicture data containing at least one I (Intra) picture that is a picturewhich has been encoded without other pictures (frames/fields) beingreferred to. A GOP can be reproduced independently of other data.

(iv) Packs

A pack has a fixed size of 2 KB, and can be classified as a Video Pack,an Audio Pack, or a Control Pack. Of these packs, a Control Pack ischaracteristic of the present invention. A Control Pack contains displaycontrol information and copy control information, and is arranged at astart of a VOBU.

1. Overview of an Optical Disc Recorder/Player

An optical disc recorder/player 1 of the present invention can be usedin place of a standard VTR, and is connected to a TV set 2 as shown inFIG. 1. The present optical disc recorder/player 1 encodes an AV signalcontained in a TV signal (or a video signal) into compressed AV digitaldata that is a VOB, records the VOB onto an optical disc, and reproducesthe VOB on the optical disc.

When recording a VOB onto an optical disc, the present optical discrecorder/player 1 extracts VBI data from an analog TV (video) signal,and inserts a Control Pack containing information shown by the extractedVBI data into each VOBU that constitutes the VOB.

When reproducing a video signal from the VOB recorded on the opticaldisc, the optical disc recorder/player 1 multiplexes the VBI data into avideo signal, which it has reproduced, according to information shown ineach Control Pack. This allows a display unit to control, for each VOBU,a display style, such as an aspect ratio, and a permission of thecopying, while the optical disc recorder/player 1 performs reproduction.

2. Construction of an Optical Disc

2.1 Physical Construction of the Optical Disc

The present embodiment describes an optical disc, using a DVD-RAM as anexample. The physical construction of the DVD-RAM is described in detailin Japanese Laid-Open Patent Application No. 8-7282 that discloses amethod to record data on both lands and grooves, and in JapaneseLaid-Open Patent Application No. 7-93873 that discloses Zone-CLV(constant linear velocity) and so will not be explained. The followingdescribes a data construction unique to the present invention when it isembodied using a DVD-RAM.

2.2 Logical Construction of the Optical Disc

FIG. 2 shows a lead-in area, a data area, a lead-out area that arepresent within a region of the DVD-RAM, and an example construction ofthe files stored in the data area.

The lead-in area contains signals used by the optical discrecorder/player 1 to stabilize the servo controlling and identificationsignals to distinguish the DVD-RAM from other types of media. Thesesignals are recorded at a start of the lead-in area (i.e., the innermostpart) of the DVD-RAM. The data area is located next to the lead-in area,and stores files containing VOBs and management information. Thelead-out area is present in the end of the DVD-RAM region (i.e., theoutermost part of the disc), and contains signals similar to thosestored in the lead-in area and other data.

At a start of the data area, volume information used for the file systemis recorded. The file system is well known in the art, and so will notbe described. The directories and files shown in this figure areaccessed according to the file system.

In this file-directory construction, a DVD_RTAV (Real Time Audio Visual)directory is present directly below a root directory. The DVD_RTAVdirectory stores one management information file and one or more AVfiles that store VOBs. All the files stored in the DVD_RTAV directorycan be classified as either a management information file or an AV file.

In the example shown in the figure, VR_MANGR.IFO is the managementinformation file, and VR_MOVIE.VRO, VR_STILL.VRO, and VR_AUDIO.VRO areAV files, with the three AV files respectively being used to recordvideo data (which may contain audio data), still picture data, and audiodata.

2.2.1 AV Files

FIG. 3 shows a data construction of the VR_MOVIE.VRO file. InVR_MOVIE.VRO, a plurality of VOBs shown as M_VOB#1 to M_VOB#N arearranged. The N is a number “1” or higher, and a VOB in thisVR_MOVIE.VRO file is called “M_VOB” to distinguish it from StillPicture_VOB (S_VOB) that is a VOB for still pictures although in thisspecification “VOB” represents an M_VOB unless otherwise specified.

Each M_VOB is composed of a plurality of VOBUs.

Each VOBU is a pack sequence that consists of a plurality of packs witha fixed size of 2 KB. Each pack can be classified as a Control Pack(hereafter C_PCK), a Video Pack (V_PCK), or an Audio Pack (A_PCK).

A C_PCK is placed at a start of a VOBU, and contains display controlinformation such as letterbox control information, and copy controlinformation relating to the permission of the copying by a VTR or thelike, and to the copy-guard system. Here, the letterbox controlinformation is used to control display of an image with an aspect ratioof 4:3 on a display screen with an aspect ratio of 16:9 or 14:9. Theoptical disc recorder/player 1 generates the display control informationand the copy control information based on VBI data multiplexed into a TV(video) signal when recording the video signal, and multiplexes DCI andCCI as the VBI data into a video signal being reproduced.

A V_PCK contains video data, and a plurality of V_PCKs contained in oneVOBU correspond to a GOP (group of pictures). A GOP is divided into thepayloads of a plurality of V_PCKs contained in the VOBU. While a GOPcontains neither audio data nor control information, a VOBU contains aC_PCK and A_PCKs in addition to the V_PCKs corresponding to at least oneGOP, and so different names are used to distinguish the two.

An A_PCK contains audio data encoded according to the MPEG audio system,the Dolby AC3, the liner PCM (pulse code modulation), or the like.V_PCKs and A_PCKs are interleaved within each VOBU.

2.2.1.1. Control Pack (C_PCK)

FIG. 4 shows a data construction of a C_PCK. As shown in the figure, theC_PCK is composed of a pack header (with a size of 14B (byte)), a systemheader (24B), and a packet (2010B). The packet is composed of a packetheader (6B), a substream ID (1B), and a data area (2003B).

The pack header contains an SCR (System Clock Reference) that determinesa position of the C_PCK within a VOBU.

The system header shows a boundary between different VOBUs. A C_PCK hasthis system header as the C_PCK is placed at a start of a VOBU.

The packet is placed into a payload of the C_PCK, and contains a packetheader, a substream ID, and a data area.

The packet header contains a stream ID “1011111b” (“b” meaning a binarynotation) that represents a “private stream 2” defined in the MPEGstandard.

The substream ID is shown as “01010000b” indicating that the pack is aC_PCK.

The data area contains display control information (hereafter, DCI),Copy Control Information (CCI), and DCI_CCI_Status information(DCI_CCI_SS) that shows the status of the DCI and the CCI.

2.2.1.1.1 Display Control Information (DCI)

FIG. 5 shows a bit configuration of DCI in a C_PCK in detail. As shownin the figure, the DCI shows an Aspect Ratio, a Subtitling Mode, and aFilm/Camera Mode.

The Aspect Ratio is 4-bit data showing how an image should be displayedaccording to a letterbox controlling.

The following describes the letterbox controlling. FIG. 6 shows arelationship between a screen size and a display image size. The aspectratio of a screen is shown as X:Y, and the aspect ratio of the displayimage is shown as X′:Y′. A display image with the aspect ratio ofX′:Y′=16:9 or 14:9 is called a letterbox image. When such a letterboximage should be displayed on a screen with the aspect ratio of, forinstance, 4:3, different display methods can be used, such as displayingthe letterbox image with black bars in the top and bottom parts of thescreen as shown in the figure, displaying the letterbox image in a toppart of the screen with a black area below, or stretching the image inthe vertical direction. The letterbox control information designatessuch a display method, and usually shows information regarding X′:Y′ andeither Y:Z or Y:Z′ measured from the center “O” of a display image.

The Aspect Ratio is shown as four bits (b4 to b7) and shows thefollowing information.

0000b: 4:3

0001b: 16:9

0001b: display a letterbox image with the aspect ratio of 14:9 in thecenter of the screen

0100b: display a letterbox image with the aspect ratio of 14:9 in a toppart of the screen

1101b: display a letterbox image with the aspect ratio of 16:9 in thecenter of the screen.

0010b: display a letterbox image with the aspect ratio of 16:9 in a toppart of the screen

1101b: display a letterbox image with the aspect ratio of 16:9 in thecenter of the screen

0111b: display a letterbox image with the aspect ratio of 14:9 on theentire screen

others: reserved

In FIG. 5, the first two values (“0000b” and “0001b”) show the aspectratios of images, and the remaining values are used for the letterboxcontrolling. FIG. 6 is an example where the letterbox image with theaspect ratio of 16:9 is displayed in the center of the screen.

The Subtitling Mode is shown as two bits (b3 and b2) of the DCI, andindicates the following information.

00b=No subtitles

01b=subtitles in active image area

10b=subtitles out of active image area

others=reserved

For the letterbox image in FIG. 6, the active image area refers to apart on the screen where the letterbox image is displayed, and the areathat is “out of active image area” is the black parts at the top orbottom of the screen. For instance, PAL (Phase Alternation by Line) uses625 scanning lines per frame for an image with an aspect ratio of 4:3,with 576 lines out of the 625 lines composing the image. On the otherhand, a PAL letterbox image with an aspect ratio of 16:9 is composed of430 lines out of the 625 scanning lines. When the Subtitling Mode shows“subtitle in active image area” for this PAL letterbox image, a subtitleis displayed on the 430-line display image. When the Subtitling Modeshows “subtitle out of active image area”, a subtitle is displayed in apart (where black is displayed) corresponding to 145 scanning lines (576minus 430 scanning lines).

Scanning lines other than the above 576 lines correspond to a VBI.

The Film/Camera Mode is shown as one bit (b0) of the DCI, and indicatesthe following information.

0b: Camera Mode

1b: Film Mode

The Film/Camera Mode is defined in PALplus that is a video imageprocessing method used in Europe, and shows whether a source material ofimages is originally recorded by a TV camera or on a movie film.

Journal of the Institute of Television Engineers of Japan vol. 49 No. 9(1995) describes the overview of the above display controlling based onthe Aspect Ratio, the Subtitling Mode, and the Film/Camera Mode, and ETS300 294 (European Telecommunications Standards) “Television Systems625-Line Television WSS” explains such display control in detail.

The above bit configuration of the DCI can be used for both PAL and NTSCimages.

2.2.1.1.2 Copy Control Information (CCI)

FIG. 7 shows a detailed bit configuration of the CCI in a C_PCK. Asshown in the figure, the CCI shows CGMS (Copy Generation ManagingSystem), APSTB (Analog Protection System Trigger Bits), and Source.

The CGMS is shown as two bits (b7 and b6) that manage generation ofcopies, and is shown as one of the following values.

00b: copying is permitted without restrictions

01b: condition is not used

10b: condition is not used

11b: copying is prohibited

The optical disc recorder/player 1 receives a video signal into whichinformation regarding the above CGMS has been multiplexed. If thereceived information shows that copying is prohibited, the optical discrecorder/player 1 cancels the recording. If the received informationshows that a first-generation copy is permitted to be generated, theoptical disc recorder/player 1 sets “11b” (showing that the copying isprohibited) as the CGMS, and performs the recording. If the informationshows that the recording is permitted without restrictions, the opticaldisc recorder/player 1 sets “00b” (showing that the recording ispermitted without restrictions) as CGMS, and performs the recording.

APS is a copy protection system developed by Macrovision Corporation foran analog video signal, and so is also called “Macrovision”. The APSTBis shown as two bits (b5 and b4) to indicate an APS copy protectionmethod used for a video signal inputted to the optical discrecorder/player 1. The settings of these two bits have the followingmeanings.

00b: APS is off

01b : type 1 of APS is on

10b : type 2 of APS is on

11b : type 3 of APS is on

Of the above types, type 1 is a method to disturb an AGC (automatic gaincontrol) circuit of a VTR, and type 2 is a method that combines theabove AGC disturbance method and a method to invert two colorstripes.Type 3 refers to a method that combines the above AGC disturbance methodand a method to invert four colorstripes. On receiving a video signalinto which information regarding the APS has been multiplexed, theoptical disc recorder/player 1 sets the APSTB based on the received APS.

The Source is shown as one bit (b3) that shows whether a source materialfor images is an analog pre-recorded package medium as follows.

0b analog pre-recorded package medium

1b :not analog pre-recorded package medium

The Source is set by a source provider, and written in VBI data of avideo signal inputted to the optical disc recorder/player 1. The Sourceis defined in CEI (Commission Electrotechnique Internationale)/IEC68801998 01 Section 3 “VBID (VBI data)”. The Source is set as “0b” (showingthat a source material is the analog pre-recorded package medium) when avideo signal inputted to the optical disc recorder/player 1 wasgenerated from a source material such as packaged software for a movielike a laserdisc pressed at a factory. Source is set as “1b” when theinputted video signal was generated based on not the analog pre-recordedpackage medium but, for instance, a material generated by a broadcaster.

2.2.1.1.3 DCI CCI Status Information (DCI_CCI_SS)

FIG. 8 shows a bit configuration of the DCI_CCI_SS contained in a C_PCK.

As shown in the figure, the DCI_CCI_SS shows DCI status (hereafterDCI_SS) and CCI status (CCI_SS).

The DCI_SS is shown as two bits that indicate which parts of the DCI arevalid as follows.

00b: entire DCI is invalid

01b: only Aspect Ratio of DCI is valid

10b: reserved (undefined)

11b: Aspect Ratio, Subtitling Mode, and Film/Camera Mode in DCI arevalid

Note that the value of DCI_SS may only be changed between “01b” and“11b” within a VOB.

The CCI_SS is shown as two bits that indicate which parts of the CCI arevalid as follows.

000b : entire CCI is invalid

001b : Source in CCI is valid

010b : APSTB in CCI is valid

011b : APSTB and Source in CCI are valid

100b : CGMS in CCI is valid

101b : CGMS and Source in CCI are valid

110b: CGMS and APS in CCI are valid

111b: CGMS, APSTB, and Source in CCI are valid

 Note: When either DCI_SS or CCI_SS is set to non-zero value, at leastone of DCI and CCI is in valid state.

2.2.2 Management Information File (VR_MANGR.IFO)

FIG. 9A shows a data construction of a VR_MANGR.IFO file shown in FIG. 2at different levels.

As shown in the figure, the VR_MANGR.IFO is also referred to as“RTR_VMG” (Real Time Recording Video Manager), and contains thefollowing seven tables and information: RTR_VMGI (RTR_VMG Information);an M_AVFIT (Movie AV File Information Table); an S_AVFIT (Still PictureAV File Information Table); ORG_PGCI (Original Program ChainInformation); a UD_PGCIT (User Defined PGC Information Table); TXTDT_MG(Test Data Manager); and an MNFIT (Manufacturer's Information Table).

The following focuses on the parts related to the “V_ATR” (VideoAttribute) information that is a characteristic of the presentinvention.

The M_AVFIT stores management information for the VR_MOVIE.VRO (AV filefor video data), and contains M_AVFITI (Movie AV File Information TableInformation), M_AVFI (Movie AV File Information), and at least one setof M_VOB_STI (Movie VOB Stream Information) likeM_VOB_STI#1˜M_VOB_STI#n, with n being either the number of VOBs in theVR_MOVIE.VRO file or a number smaller than this number of VOBs.

This number “n” becomes smaller than the number of VOBs when a singleset of M_VOB_STI is shared by a plurality of VOBs. This is to say, asingle piece of M_VOB_STI can correspond to either one VOB or aplurality of VOBs. This correspondence between a VOB and a piece ofM_VOB_STI is shown by “M_VOB_STIN” (M_VOB_STI number) that is set in VOBinformation (VOBI), which is contained in the M_AVFI and is given toeach VOB. FIG. 9C shows the M_VOB_STIN contained in M_AVFI. The M_AVFIcontains, for each VOB, a piece of VOBI (shown as “M_VOBI” in thefigure) that shows information on the VOB, such as a time map andM_VOB_GI (General Information). The M_VOB_GI shows a time at which astart of the VOB was recorded, an M_VOB_STIN, or the like.

Each piece of M_VOB_STI for one or more VOBs in the VR_MOVIE.VRO fileshows the following information relating to the VOBs: a V_ATR (VideoAttribute); an AST_Ns (Number of Audio Streams); an SPST_Ns (Number ofSub-Picture Streams); an A_ATRO (Audio Attribute for Stream #0); anA_ATR1 (Audio Attribute for Stream #1); an SP_ATR (Sub-PictureAttribute); and an SP_PLT (Sub-Picture Color Palette).

The V_ATR shows the attribute of images of a VOB in the VR_MOVIE.VROfile. FIG. 9B shows the bit configuration of the V_ATR. As shown in thefigure, the V_ATR is composed of a Video Compression Mode, a TV System,an Aspect Ratio, an Application Flag, a Line21_Switch_1, aLine21_Switch_2, and a Video Resolution.

The Video Compression Mode is shown as two bits, with “00b” indicatingthat the VOB has been compressed according to MPEG 1 and “01b”indicating that the VOB has been compressed according to MPEG 2.

The TV System is shown as two bits, with “00b” indicating 525/60(representing the number of scanning lines per frame/the number offields per second) for the VOB and “01b” indicating 625/50. The TVsystem shown by the former bit set is the NTSC system, and the latter isthe PAL or SECAM (Sequential Couleur a Memoire) TV system.

The Aspect Ratio is shown as two bits, with “00b” indicating a ratio 4:3and “01b” indicating a ratio 16:9 for the VOB. When this Aspect Ratiofor a VOB is interpreted, the Application Flag is used to prevent acontradiction with the Aspect Ratio for a VOBU in a C_PCK fromoccurring.

The Application Flag is two bit data and shows whether the aspect ratioshown in the V_ATR or in a C_PCK should be used. When the ApplicationFlag is shown as “00b”, a video stream is coded with Aspect Ratiospecified in the V_ATR. In this case, the VOB does not contain anyC_PCK, or the aspect ratio in a C_PCK is ignored. When the ApplicationFlag is shown as “01b”, a video stream may be coded with Aspect Ratiospecified in this V_ATR, but the actual Aspect Ratio is recorded in aC_PCK if the C_PCK exists in the VOB. This is to say, the aspect ratioshown in each C_PCK is used when the two aspect ratios shown in theV_ATR and the C_PCK are different. If no C_PCK exists in a VOB, theaspect ratio shown in the V_ATR is used for images of the VOB. When asingle V_ATR (a set of M_VOB_STI) corresponds to a plurality of VOBs andsome of these VOBs have a C_PCK while others do not, the aspect ratioshown in a C_PCK is recognized as the aspect ratio for a VOB thatcontains a C_PCK, and the aspect ratio in the V_ATR is recognized for aVOB that contains no C_PCK.

Note that when DCI_SS is set as “01b” or “11b”, the Application Flag inV_ATR in M_VOB_STI specified by VOBI for this M_VOB shall be set to“01b” and when DCI_SS is set to “00b”, Application Flag in V_ATR inM_VOB_STI specified by VOBI for this M_VOB shall be set to “00b”.

The Line21_Switch_(—)1 is shown as one bit, with “1b” indicating thatthe VOB contains data (which is often closed caption data) that has beenmultiplexed into the 21st horizontal scanning line in the first field ofa frame, with “0b” indicating that the VOB contains no such data.

The Line21_Switch_2 is the same as the Line21_Switch_1 except that theformer is provided corresponding to the second field of a frame.

The Video Resolution is shown as three bits that indicate the resolutionof images for the VOB. For the VOB conforming to the above TV system of“525/60”, when the three bits are “000b”, “001b”, “010b”, “011b”,“100b”, and “101b”, the resolution for the VOB is 720×480, 704×480,352×480, 352×240, 544×480, and 480×480, respectively. For the VOBconforming to the above TV system with “625/50”, when the three bits are“000b”, “001b”, “010b”, “011b”, “100b”, and “101b”, the resolution forthe VOB is 720×570, 704×576, 352×576, 352×288, 544×576, and 480×576,respectively.

As the V_ATR is contained in the VR_MANGR.IFO file provided separatelyfrom the AV files, the optical disc recorder/player 1 can read theattribute of each VOB without reproducing the AV files. In this way, theattribute for each VOB is set in the V_ATR, and the attribute for eachVOBU is set in a C_PCK.

3. Construction of Optical Disc Recorder/Player 1

FIG. 10 is a block diagram showing the construction of the optical discrecorder/player 1. As shown in the figure, the optical discrecorder/player 1 comprises the following elements: a high frequency(HF) receiving unit 71; an image demodulator 72; a VBID (VBI data)demodulator 73; a buffer 81; a switch 82; a DVD recorder 75; a datatransfer unit 83; and a VBI signal multiplexer 84.

The HF receiving unit 71 receives a desired TV signal via a broadcastwave.

The image demodulator 72 demodulates the TV signal received by the HFreceiving unit 71, converts the demodulated TV signal into a videosignal and an audio signal, and outputs them via the buffer 81 and theswitch 82 to the DVD recorder 75.

The VBID demodulator 73 detects VBID contained in the video signal thathas been demodulated by the image demodulator 72, generates DCI data ,CCI data, and DCI_CCI_SS data based on the detected VBID, and outputsthem to the DVD recorder 75. A time lag between the output of the videosignal and the audio signal by the image demodulator 72, and the outputof the DCI data, CCI data, and the DCI_CCI_SS data by the VBIDdemodulator 73 is absorbed by the buffer 81 and the switch 82 so as tohave the video signal, the audio signal, the DCI data, the CCI data, andthe DCI_CCI_SS data inputted synchronously to the DVD recorder 75.

The DVD recorder 75 receives the video signal and audio signal via thebuffer 81 and the switch 82 from the image demodulator 72, compressesthem as VOBs, and records the VOBs onto a DVD-RAM. When doing so, theDVD recorder 75 receives the DCI data, CCI data, DCI_CCI_SS data fromthe VBID demodulator 73, and records DCI, CCI, and DCI_CCI_SS for eachVOBU onto the DVD-RAM. The DVD recorder 75 also decodes a VOB on aDVD-RAM to obtain an analog AV signal which it outputs to the VBI signalmultiplexer 84. While outputting this analog signal, the DVD recorder 75extracts DCI and CCI from VOBUS, and outputs them to the VBI signalmultiplexer 84.

The VBI signal multiplexer 84 receives the analog video signal, the DCI,and the CCI from the DVD recorder 75, and multiplexes VBID that is basedon the received DCI and CCI into the analog video signal during a VBI.

The data transfer unit 83 receives a digital AV signal that has beendecoded by the DVD recorder 75, and outputs it to a device, such as a PC(personal computer). The data transfer unit 83 determines whether toperform the outputting based on the CCI that has been inputted from theDVD recorder 75.

3.1 VBID Demodulator

FIG. 11 is a block diagram showing the detailed construction of the VBIDdemodulator 73, which comprises the following elements: a VBID detectingunit 731, a DCI generating unit 732, an MV (Macrovision) detecting unit733, and a CCI generating unit 734.

The VBID detecting unit 731 receives an analog video signal from theimage demodulator 72, and detects VBID contained in each field of theanalog video signal. The following explanation assumes that 20-bit VBIDis multiplexed into the 20th and 278th horizontal-scanning lines of anNTSC analog video signal and that 13-bit VBID is multiplexed into the23rd horizontal scanning line of a PALplus analog video signal. Theabove 20-bit VBID contains the following bits: two bits (b1 and b2)showing Aspect Ratio or letterbox control information; two bits (b7 andb8) showing CGMS; two bits (b9 and b10) showing APSTB; and one bit (b11)showing whether a source medium for an image for the field is the analogpre-recorded medium. On the other hand, the above 13-bit VBID containsthe following bits: four bits (b0 to b3) showing Aspect Ratio orletterbox control information; one bit (b4) showing the Film/CameraMode; and two bits (b9 and b10) showing the Subtitling Mode. The VBIDdetecting unit 731 detects the above 20-bit VBID from an NTSC signal,and the 13-bit VBID from a PAL signal.

The MV detecting unit 733 detects whether Macrovision is used as a copyprotection method for the analog video signal which has been inputtedfrom the image demodulator 72.

3.1.1 DCI Generating Unit

The DCI generating unit 732 includes a one-byte internal DCI registerand a two-bit internal DCI_SS register. After generating data for DCIand DCI_SS based on the detected VBID, the DCI generating unit 732 setsthe DCI data and DCI_SS data in the above two registers, which thenoutput the stored data to the DVD recorder 75.

FIG. 12 is a flowchart showing the detailed processing by the DCIgenerating unit 732 to generate the DCI data and DCI_SS data. The DCIgenerating unit 732 judges whether the VBID detecting unit 731 hasdetected VBID (step S121). If VBID has been detected and the currentanalog video signal is an NTSC signal (step S122), the DCI generatingunit 732 sets “01” in the DCI_SS register (step S123). This is becausethe NTSC signal contains VBLD of which only the Aspect Ratio can be setas valid DCI.

Following this, the DCI generating unit 732 converts the two bits (b1and b2) of the 20-bit VBID, which has been detected by the VBIDdetecting unit 731, according to a conversion table shown in FIG. 13. Asa result, the two bits are converted into four bits. The DCI generatingunit 732 then sets the four bits in b4-b7 of the DCI register as theAspect Ratio, and “0” in the remaining bits of the DCI register as theSubtitling Mode and the Film/Camera Mode (Step S124). The DCI generatingunit 732 sets “00b” in the DCI_SS register if the above two bits (b1 andb2) are “11b”.

On the other hand, when judging in step 122 that the analog video signalis a PAL signal, the DCI generating unit 732 sets “11b” in the DCI_SSregister (step S125) because the PAL signal contains VBID of which theAspect Ratio, the Subtitling Mode, and the Film/Camera Mode can be setas valid DCI.

Following this, the DCI generating unit 732 converts four bits (b0 to b3for the Aspect Ratio), two bits (b9 and b10 for the Subtitling Mode),and one bit (b4 for the Film/Camera Mode) of the 13-bit VBID, accordingto conversion tables shown in FIGS. 14-16. The DCI generating unit 732then sets the converted bits in the DCI register as the Aspect Ratio,the Subtitling Mode, and the Film/Camera Mode (step S126).

When the VBTD detecting unit 731 has not detected any VBID (step S121),the DCI generating unit 732 sets “0” in all the bits of the DCI registerand the DCI_SS register (step S127).

After setting data in the DCI register and the DCI_SS register in thisway, the DCI generating unit 732 outputs all the data to the DVDrecorder 75 (step S128).

3.1.2 CCI Generating Unit

The CCI generating unit 734 includes a one-byte internal CCI registerand a three-bit internal CCI_SS register, and generates CCI data andCCI_SS data based on the VBID that has been detected by the VBIDdetecting unit 731 and on a detection result generated by the MVdetecting unit 733. The CCI generating unit 734 then sets the generatedCCI data and CCI_SS data in the above two registers, and outputs thedata in the registers to the DVD recorder 75.

FIG. 17 is a flowchart showing the detailed processing by the CCIgenerating unit 734 to generate the CCI data and CCI_SS data. On judgingthat an analog video signal inputted from the image demodulator 72 is anNTSC signal and that the VBLD detecting unit 731 has detected the VBID(step S171), the CCI generating unit 734 sets “111B” in the CCI_SSregister (step S172). These bits can be updated through the followingprocessing. When the judging that two bits (b7 and b8) of the 20-bitVBJD that has been detected by the VBID detecting unit 731 are “11b”(indicating that copying is prohibited) (step S173), the CCI generatingunit 734 outputs a recoding stop signal to the switch 82 and the DVDrecorder 75 (step S174) so that the switch 82 becomes OFF and the analogvideo signal is not outputted to the DVD recorder 75. As a result, theDVD recorder 75 stops the processing that records data for the DVD-RAM.Thereafter, when receiving VBID that does not prohibit copying, the CCIgenerating unit 734 clears the recording prohibition, clears the storeddata in the buffer 81, sets the switch 82 on, and resumes the recordingprocessing.

After giving the “NO” judgement in step S173, the CCI generating unit734 further judges if the above two bits (b7 and b8) of the 20-bit VBLDare “01b” (indicating that the CGMS is undefined) (step S175). If so,the CCI generating unit 734 sets “011b” in the CSI_S register (stepS176). When the MV detecting unit 733 has judged that Macrovision is notused for the video signal (step S177), the CCI generating unit 734changes the bit (b2) in the CCI_SS register to “0” (step S178).

After this, the CCI generating unit 734 converts sets of bits (b7-b8,b9-b10, and b11) into the CGMS, the APSTB, and the Source usingconversion tables shown in FIGS. 18-20 (step S179), and sets them in theCCI register (step S179).

On the other hand, when the video signal from the image demodulator 72is not an NTSC signal and the VBID detecting unit 731 has not detectedany VBID from the signal (step S171), the CCI generating unit 734 sets“0” in the all the bits of the CCI register and the CCI_SS register(step S180) since no CCI information exists for the video signal.

After performing the above operations for a field of the video signalsent by the image demodulator 72, the CCI generating unit 734 and theDCI generating unit 732 output the data stored in the CCI register, theDCI register, the CCI_SS register, and the DCI_SS register to the DVDrecorder 75. Hereafter, data outputted from the CCI register andDCI_register are called CCI data and DCI data, respectively, and dataoutputted from the DCI_SS register and the CCI_SS register arecollectively called DCI_CCI_SS data.

3.2 DVD Recorder

FIG. 21 is a block diagram showing the detailed construction of the DVDrecorder 75, which includes the following elements: a user interface(U/I) unit 1401; a system controlling unit 1402; an A/V signal inputtingunit 1403; an encoding unit 1404; an outputting unit 1405; a decodingunit 1406; a track buffer 1407; a drive 1408; and a control informationinputting unit 1409.

The U/I unit 1401 includes an operation panel and a remote controlsignal photoreceiver, and receives a user operation via the operationpanel and a remote control signal via the photoreceiver from a remotecontroller as shown in FIG. 1.

The system controlling unit 1402 receives an instruction from the U/Iunit 1401 such as a recording start instruction, a recording endinstruction, a playback start instruction, or a playback endinstruction, and controls the overall processing in accordance with thereceived instruction. When the recording is performed, the systemcontrolling unit 1402 receives the DCI data, CCI data, and theDCI_CCI_SS data (hereafter these three sets of data are collectivelycalled “control information data”) that corresponds to one field fromthe control information inputting unit 1409, and determines contents ofcontrol information that should be inserted into a C_PCK at a start of aVOBU, and outputs the control information to the encoding unit 1404.This is to say, the system controlling unit 1402 receives the controlinformation data that corresponds to at least one field (i.e., {fraction(1/60)} or {fraction (1/50)} second), and outputs control informationcorresponding to a VOBU (i.e., 0.4-1.0 second) to the encoding unit1404. A field that corresponds to VBID whose content is different fromVBID of a preceding field is not necessarily located at a start of aVOBU. The system controlling unit 1402 detects changes in the controlinformation data, which is inputted for each field, during apredetermined period for which fields in front of and behind fieldscorresponding to a start of a current VOBU are inputted, and has themost suitable control information inserted at the start of the currentVOBU.

The A/V signal inputting unit 1403 receives a video signal and an audiosignal via the buffer 81 and the switch 82 from the image demodulator72, and outputs them to the encoding unit 1404.

The encoding unit 1404 generates a V_PCK and an A_PCK by compressing thevideo signal and audio signal inputted from the A/V signal inputtingunit 1403, and generates a C_PCK based on the control informationinputted from the system controlling unit 1402. The encoding unit 1404then generates a VOB made up of VOBUs that each have a C_PCK at a start.The above operations are performed under the control of the systemcontrolling unit 1402.

The track buffer 1407 temporarily stores a VOB generated by the encodingunit 1404 when recording is to be performed, and stores a VOB read fromthe DVD-RAM when playback is to be performed.

When a DVD-RAM is loaded and playback or recording is performed, thedrive 1408 performs the servo control and the roll control when therecording or the playing is performed. The drive 1408 writes a VOBstored in the track buffer 1407 onto the DVD-RAM via an optional pickup,and reads a VOB from the DVD-RAM into the track buffer 1407 via theoptical pickup. In reality, however, a write onto and a read from theDVD-RAM are performed in a unit of an ECC (Error Correcting Code) block(i.e., sixteen sectors that are equal to 2 KB×16 packs). This is notrelated to the essence of present invention and so will not bedescribed.

The decoding unit 1406 receives a VOB that has been read from theDVD-RAM and sent from the track buffer 1407, decompresses the VOB toobtain a digital video signal and a digital audio signal. At the sametime, the decoding unit 1406 extracts control information from the C_PCKin the VOB, and outputs it via the outputting unit 1405 to the VBIsignal multiplexer 84. The decoding unit 1406 performs the aboveoperations under the control of the system controlling unit 1402.

The outputting unit 1405 converts the digital video signal and audiosignal into analog forms, and output them to the VBI signal multiplexer84. The outputting unit 1405 also receives the control information fromthe decoding unit 1406, and outputs it to the VBI signal multiplexer 84.

The control information inputting unit 1409 receives the controlinformation data from the VBID demodulator 73 and outputs it to thesystem controlling unit 1402.

3.2.1 Encoding Unit

FIG. 22 is a block diagram showing the detailed construction of theencoding unit 1404 shown in FIG. 21. The encoding unit 1404 contains thefollowing elements: a video encoder 1501; a video data buffer 1502; anaudio encoder 1503; an audio data buffer 1504; a control informationbuffer 1505; a system time clock (STC) unit 1506; an encoder controllingunit 1507; and a system encoder 1508.

The video encoder 1501 receives a video signal from the A/V signalinputting unit 1403, compresses (encodes) the video signal into MPEG2video data, and places the MPEG2 video data into the video data buffer1502.

The audio encoder 1503 receives an audio signal from the A/V signalinputting unit 1403, compresses (encodes) the audio signal, and placesthe compressed audio data into the audio data buffer 1504.

The control information buffer 1505 temporarily stores the controlinformation inputted from the system controlling unit 1402.

The STC unit 1506 generates a clock signal (a system time clock)according to which the encoding is performed.

The encoder controlling unit 1507 controls the overall encodingoperations of the encoding unit 1404. According to an encoding startinstruction and an encoding end instruction from the system controllingunit 1402, the encoder controlling unit 1507 starts and ends theencoding, and informs the system controlling unit 1402 of the end of theencoding whenever one VOBU has been generated. When receiving aninstruction to insert control information into a start of a VOBU fromthe system controlling unit 1402, the encoder controlling unit 1507 hasthe control information buffer 1505 output control information to thesystem encoder 1508.

The system encoder 1508 extracts compressed video data and compressedaudio data that have the same size as the payload of a pack (or apacket), and control information from the video data buffer 1502, theaudio data buffer 1504, and the control information buffer 1505,respectively. The system encoder 1508 then generates a C_PCK, a V_PCK,and an A_PCK, produces a VOBU by interleaving generated packs, andoutputs the generated VOBU to the track buffer 1407.

3.2.1.1 System Encoder

FIG. 23 is a block diagram showing the detailed construction of thesystem encoder 1508. As shown in the figure, the system encoder 1508contains a virtual playback time clock unit 1601, a video packing unit1602, virtual decoder buffers 1603 and 1605, an audio packing unit 1604,a C_PCK packing unit 1606, and an interleaving unit 1607.

The virtual playback time clock unit 1601 generates a virtual playbacktime based on which time stamps, such as an SCR, a DTS (Decode TimeStamp), and a PTS (Presentation Time Stamp), are given to each pack.Here, the DTS shows a time at which the decoding unit 1406 should startdecoding a pack during playback, and the PTS shows a time at which videodata or audio data that has been decoded from the pack should bepresented to the user when playback is performed.

The video packing unit 1602 extracts compressed video data from thevideo data buffer 1502, and generates a V_PCK containing the extractedvideo data. When doing so, time stamps are set so as to avoid underflowsand overflows in the virtual decoder buffer 1603.

The virtual decoder buffer 1603 is a virtual buffer used in simulationof how much video data will accumulate in a buffer used as a temporarystorage during playback.

The audio packing unit 1604 extracts compressed audio data from theaudio data buffer 1504, and generates an A_PCK containing the extractedaudio data. When doing so, time stamps are set so as to avoid underflowsand overflows in the virtual decoder buffer 1605.

The virtual decoder buffer 1605 is a virtual buffer used in simulationof how much audio data will accumulate in a buffer used as a temporarystorage during playback.

The C_PCK packing unit 1606 generates a C_PCK as shown in FIG. 4 foreach VOBU using control information (i.e., DCI, CCI, and DCI_CCI_SS)inputted from the control information buffer 1505, and assigns the C_PCKan SCR with the lowest value of all the packs that will make up theVOBU.

The interleaving unit 1607 extracts packs one by one in ascending orderof SCR out of the packs that have been generated by the C_PCK packingunit 1606, the video packing unit 1602, and the audio packing unit 1604,produces a pack sequence, that is, a VOBU by arranging the above packsin order of the above extraction, and outputs the generated VOBU to thetrack buffer 1407. Note that a C_PCK is given an SCR with the lowestvalue of all the packs that make up a VOBU. As a result, a C_PCK isalways placed at a start of a VOBU.

3.2.1.2 Encoding Control Flow

FIG. 24 is a flowchart showing the encoding control by the systemcontrolling unit 1409 shown in FIG. 21.

The system controlling unit 1402 receives, from the U/I unit 1401, anotification showing that the U/I unit 1401 has received a recordingstart instruction (step S241). The system controlling unit 1402 thenjudges if it has received valid control information from the controllinginformation inputting unit 1409 (i.e., the unit 1402 judges if all thebits of at least one of the DCI_SS data and the CCI_SS data are not “0”)(step S242). If so, the system controlling unit 1402 examines how thereceived control information data for a plurality of fields to becontained in a VOBU changes, determines the content of controlinformation suited to be placed at a start of the VOBU, and writes thecontrol information into the control information buffer 1505 (stepS243). For instance, when there is no change in control information datafor five fields that proceed a picture (i.e., field) to be placed at astart of the VOBU, the system controlling unit 1402 writes this controlinformation data as control information into the control informationbuffer 1505.

Note that in this step S243 the system controlling unit 1402 may simplywrite control information for fields that correspond to a start of aVOBU into the control information buffer 1505 without examining thechanges in the control information. This can reduce the operation loadof the system controlling unit 1402.

The encoding unit 1404 places a C_PCK that contains this controlinformation at a start of the VOBU.

The system controlling unit 1402 instructs the encoding unit 1404 (theencoder controlling unit 1507 to be exact) to start the encoding (stepS244), and at the same time controls the drive 1408 to have it recordthe result of the encoding onto the DVD-RAM.

Following this, the system controlling unit 1402 judges if it hasreceived from the encoder controlling unit 1507 a notification showingthat the encoding has been completed for a VOBU (step S245), and furtherjudges if it has received from the U/I unit 1401 a notification showingthat the U/I unit 1401 has received a recording end instruction (stepS246).

When the encoding for the VOBU has been completed to (step S245), thesystem controlling unit 1402 controls to start the encoding for the nextVOBU by performing the operations from steps S242-S244. As a result, thenext VOBU containing a C_PCK at a start of the VOBU is generated.

If a recording end instruction has been received (step S246), the systemcontrolling unit 1402 instructs the encoding unit 1404 to stop theencoding, and generates M_VOB_STI for VOBs that have been recorded onthe DVD-RAM (step S247). In generating the M_VOB_STI, the systemcontrolling unit 1402 sets the Application Flag in the M_VOB_STI as“01b” (showing that images of the current VOB have the aspect ratioshown in each C_PCK) if the Aspect Ratio shown in a plurality of C_PCKscontained in the current VOB changes. When the aspect ratio remains thesame within the VOB, the system controlling unit 1402 sets theApplication Flag as “00b” (showing that images of the current VOB havethe same aspect ratio shown in the V_ATR). When setting “00b” as theApplication Flag, the system controlling unit 1402 sets an aspect ratiothat has been inputted from the control inputting unit 1409 in theAspect Ratio in the V_ATR. When setting “01b” as the Application Flag,the system controlling unit 1409 selects a suitable aspect ratio fromaspect ratios that have been inputted from the control informationinputting unit 1409, and sets the selected aspect ratio as the AspectRatio in the V_ATR. The “suitable” aspect ratio may be an aspect ratioused when the recording starts or an aspect ratio that has been usedmost frequently during the recording.

Following this, the system controlling unit 1402 updates or generates aVR_MANGR.IFO management information file to insert the generatedM_VOB_STI into the VR_MANGR.IFO (step S248).

In this way, the system controlling unit 1402 generates a VOBU in whicha C_PCK containing control information is placed at a start of theC_PCK, and updates the VR_MANGR.IFO containing a V_ATR.

On the other hand, when the system controlling unit 1402 has judged thatit has not received any valid control information data in step S242, theunit 1402 skips the processing in step S243 and performs the processingin step S244. As a result, the encoding unit 1404 generates a VOBUwithout inserting a C_PCK into a start of the VOBU. In the presentembodiment, the encoding unit 1404 does not insert a C_PCK into any ofthe VOBUs that make up a VOB if no C_PCK is inserted into a VOBU at thestart of the VOB.

3.2.2 Decoding Unit

FIG. 25 is a block diagram showing the detailed construction of thedecoding unit 1406 shown in FIG. 21. As shown in the figure, thedecoding unit 1405 includes a demultiplexer 1702, a video buffer 1703, avideo decoder 1704, a reordering buffer 1705, a switch 1706, an audiobuffer 1707, an audio decoder 1708, and a control information outputtingunit 1709.

When playback is to be performed, the demultiplexer 1702 receives a VOBfrom the track buffer 1407, and places the payload (i.e., packet) ofeach pack making up the VOB into the control information outputting unit1709, the video buffer 1703, or the audio buffer 1707 in accordance witha type of the pack.

The video decoder 1704 extracts a packet from the video buffer 1703 anddecodes the extracted packet. The above extraction is performed when aDTS written in a packet stored at a start of the video buffer 1703 isequal to the STC.

The reordering buffer 1705 buffers a plurality of sets of decoded videodata and is used when the plurality of sets of the video data arerearranged to change the decoding order of the video data into thedisplaying order for pictures.

The switch 1706 receives the decoded video data from the video decoder1704 and the reordering buffer 1705, and outputs video data thatcorresponds to one picture to the outputting unit 1405 and the datatransfer unit 83. This output is performed when a PTS written in apacket is equal to the STC.

The audio decoder 1708 extracts a packet from the audio buffer 1707, anddecodes the extracted packet. This extraction is performed when a PTSwritten in a packet stored at a start of the audio buffer 1707 is equalto the STC. The audio decoder outputs the result of this decoding to theoutputting unit 1405 and the data transfer unit 83 immediately after thedecoding.

The control information outputting unit 1709 receives a packet of aC_PCK from the demultiplexer 1702, and outputs control information(i.e., DCI, CCI, and DCI_CCI_SS) in the received packet to theoutputting unit 1405 and the data transfer unit 83. Since a C_PCK ispresent at a start of each VOBU, the control information outputting unit1709 outputs control information to the outputting unit 1405 wheneverone VOBU has been decoded.

This control information is outputted via the outputting unit 1405 tothe VBI signal multiplexer 84. On receiving the control information andan analog video signal from the outputting unit 1405, the VBI signalmultiplexer 84 multiplexes VBID into the analog video signal during aVBI based on the control information. More specifically, the VBI signalmultiplexer 84 receives the control information corresponding to oneVOBU, and holds the control information until it receives the nextcontrol information. The VBI signal multiplexer 84 multiplexes VBIDduring the VBIs of all the fields based on this held controlinformation.

As has been described, the optical disc recorder/player 1 of the aboveembodiment inserts, as a C_PCK, display control information and copycontrol information that have been multiplexed during VBIs into VOBUswhen converting a television (or video) signal to record it onto thepresent optical disc. As a result, the present optical discrecorder/player can control, for each VOBU, the recording onto and theplaying from the optical disc using the display control information andcopy control information. To generate such VOBUs, the system controllingunit 1402 merely needs to output control information to the encodingunit 1404 whenever the system controlling unit 1402 has been notified bythe encoding unit 1404 that the encoding for one VOBU has beencompleted, and the encoding unit 1404 merely needs to insert one C_PCKinto a start of each VOBU. As this operation to insert a C_PCK issimple, the operation load of the encoding unit 1404 is very small.

Aspect Ratio set in DCI of control information is used by the opticaldisc recorder/player 1 as follows. When recording, for instance, a movieprogram with an aspect ratio of 16:9 together with commercials with anaspect ratio of 4:3 which are broadcasted at intervals of the movie, theoptical disc recorder/player 1 sets “16:9” as the Aspect Ratio shown inDCI of a C_PCK in each VOBU that correspond to the movie, and “4:3” asthe Aspect Ratio in a C_PCK of each VOBU that corresponds to thecommercials. In this way, the aspect ratio for each VOBU is recorded.When reproducing this movie, the optical disc recorder/player 1 has theVBI signal multiplexer 84 multiplex VBID containing these aspect ratiosinto a video signal.

The letterbox control information set in the Aspect Ratio is used by theoptical disc recorder/player 1 as follows. When recording a movie giventhe letterbox control information showing that images for the movie havean aspect ratio of 16:9 and should be displayed in a top part of thescreen, together with commercials given the letterbox controlinformation showing that the commercials have an aspect ratio of 16:9and should be displayed in the center of the screen, for instance, theoptical disc recorder/player 1 inserts suitable letterbox controlinformation into a C_PCK of each VOBU based on VBI data. As a result,the letterbox controlling changes when the content of the program isswitched from the movie to a commercial or vice versa. When reproducingthese recorded programs, the optical disc recorder/player 1 has the VBIsignal multiplexer 84 multiplex VBID containing the letterbox controlinformation into a video signal. Accordingly, letterbox controlinformation for each VOBU can be effectively used even after programsare recorded on the optical disc.

Subtitling Mode set in DCI of the control information is used by theoptical disc recorder/player 1 as follows. When consecutively recording,for instance, programs A to C that have subtitling modes showing thatsubtitles should be displayed in active image area, that no subtitlesshould be displayed, and that subtitles should be displayed out ofactive image area, respectively the optical disc recorder/player 1records the programs A to C as one VOB, in which VOBUs corresponding toeach program have a C_PCK containing the Subtitling Mode appropriate forthe program. Accordingly, Subtitling Mode can be effectively used foreach program even after the program is recorded on the optical disc.

Film/Camera Mode set in DCI of the control information is used asfollows. An image recorded on a film is usually composed of 24 fieldsper second, while an image recorded by a TV camera for NTSC is composedof 30 frames (i.e., 60 fields). When the Film Mode is set for a videosignal, the number of frames for the video signal has been changed from24 frames to 30 frames per second as a result of six frames being addedto the original 24 frames.

Film/Camera Mode is useful when another recording device re-encodes ananalog video signal or digital video data outputted from the opticaldisc recorder/player 1. In more detail, when the optical discrecorder/player 1 sets Film Mode and Camera Mode in each VOBU thatcorresponds to a movie program and a commercial, respectively, andreproduces a VOB made up by the two VOBUs for the commercial, the VBIsignal multiplexer 84 or the data transfer unit 83 outputs an analogvideo signal or a digital video data. When the other recording device inthe periphery of the optical disc player/recorder 1 receives this videosignal or video data, it can detect whether Film Mode or Camera Mode isgiven to the signal or the data. The recording device therefore candistinguish the added six frames from other 24 frames when re-encodingthe signal or data. This can prevent the image quality from beingdegraded as a result of the re-encoding. In this way, the optical discrecorder/player 1 can provide Film/Camera Mode for each VOBU with otherrecording devices.

CGMS set in CCI of the control information is used as follows.

When VBID detected by the VBID detecting unit 731 shows prohibition ofthe copying, the switch 82 becomes off and the DVD recorder 75 stops therecording. As the copying can be prohibited in units of VOBUs, thecopyright of productions such as a program can be protected.

When VBID detected by the VBID detecting unit 731 shows thatfirst-generation copies can be generated, the CCI generating unit 734sets “copying is prohibited” in the CCI data while the DVD recorder 75performs the recording onto the optical disc. Accordingly, the copyingcan be controlled for each VOBU as desired by a producer or an owner ofa program or the like, such as by merely allowing the first-generationcopies to be generated.

When VBID detected by the VBID detecting unit 731 shows that the copyingis permitted without restrictions, the CCI generating unit 734 sets“copying is permitted without restrictions” in the CCI data, while theDVD recorder 75 performs the recording onto the optical disc.Accordingly, the copying can be controlled for each VOBU as desired bythe producer or the owner of the program such as by allowing the copyinglimitlessly.

APSTB in CCI of the control information is used as follows. APS is atechnique to degrade quality of images that have been recorded by ananalog VTR without affecting reproduction by a TV so as to prevent theimages from being recorded by the analog VTR and protect the copyrightfor the images. When recording an analog video signal to which APS isapplied, the optical disc recorder/player 1 sets APSTB in the CCI foreach VOBU. When reproducing the video signal, the VBI signal multiplexer84 apply APS to the video signal based on APSTB set in the CCI. Thismakes is possible to control the recording by the analog VTR for eachVOBU. In this way, the copyright can be protected in units of VOBUsusing the APS. Accordingly, the copying control such as allowing thecopying of only a start of a program or a part of a commercial can beperformed.

4. Modified Examples

The TV set 2 and the optical disc recorder/player 1 shown in FIG. 1 maybe the same device, such as by integrating the optical discrecorder/player 1 into the TV set 2.

The above embodiment describes the optical disc recorder/player 1 of thepresent invention to be used in place of a standard VTR as shown in FIG.1 although the present optical disc recorder/player may be embodied byan information processing device such as a personal computer (PC) thatincludes a DVD-RAM drive unit, a video capture board (or a TV tunerboard), and an MPEG encoder/decoder. In this case, the VBI datamultiplexer 73 and the VBI signal multiplexer 84 may be included in thevideo capture board or the TV tuner board, and the MPEG encoder/decodermay encode and decode a VOB containing C_PCKs. This MPEG encoder/decoderdoes not have to be hardware and may achieved by software that encodesand decodes a VOB.

The above information processing device may record and reproduce a VOBcontaining C_PCKs by executing a recording program and a reproducingprogram. These recording and reproducing programs may be stored into acomputer-readable recording medium to be executed by other similarhardware so that the optical disc recorder/player of the aboveembodiment can be achieved.

A C_PCK in the above embodiment can be also called “RDI_PCK” (Real TimeData Information Pack), and may additionally contain information such asa presentation start time of the first video field in a VOBU, arecording time (duration) of the VOBU, and manufacturer's informationshowing information such as relating to a program producer.

The optical disc recorder/player 1 of the above embodiment receives abroadcast wave and demodulates the broadcast wave to obtain a TV signalby using the HF receiving unit 71 and the image demodulator 72. Theoptical disc recorder/player 1 may also contain an inputting unit forreceiving an analog video signal such as for S-VHS and outputting thereceived analog video signal to the buffer 81 and the VBI datademodulator 73.

V_ATR of the above embodiment may contain all the contents of DCI, CCI,and DCI_CCI_SS together with application flags that correspond to AspectRatio, Subtitling Mode, Film/Camera Mode, CGMS, APSTB, and Source. As aresult, control information for each VOB and VOBU can be set in V_ATRand a C_PCK, respectively, with application flags showing whethercontrol information in the V_ATR or the C_PCK should be used.

As mentioned earlier, M_VOB_STI that contains a V_ATR can be shared by aplurality of VOBs. In this case, the system controlling unit 1402performs operations in step S248 in FIG. 24 as follows. The unit 1402compares M_VOB_STI generated in step S247 with other M_VOB_STI presentin the management information file to detect whether M_VOB_STI that hasthe same content as the generated M_VOB_STI exists. When detecting thatsuch M_VOB_STI exists, the system controlling unit 1402 does not insertthe generated M_VOB_STI into the management information file in stepS248, and instead sets the number showing the M_VOB_STI present in thefile in VOBI that corresponds to the current VOB that has been recorded.When M_VOB_STI is shared by a plurality of VOBs in this way, it becomespossible to prevent a size of the management information file fromcontinuing to increase.

In the above embodiment, every VOBU that makes up a VOB either containsa C_PCK or contains no C_PCKs at all. This is desirable in that theprocessing by the DVD recorder 75 to generate a VOBU can be simplifiedand so the operation load of the DVD recorder 75 can be reduced. It isalternatively possible that a VOB is composed of VOBUs some of whichcontain a C_PCK and some of which does not. In this case, controlinformation contained in a VOBU may be used for other VOBUs that do notcontain C_PCK and that are placed behind the VOBU. This is useful inthat a data size of each VOB can be reduced.

In the above embodiment, the VBI data multiplexer 73 outputs controlinformation corresponding to each field to the DVD recorder 75. Beforeoutputting the control information to the DVD recorder 75, the VBI datamultiplexer 73 may judge whether the control information is reliable orwhether the same control information has been sent for a predeterminedduration, and may output it to the DVD recorder 75 only when giving theaffirmative judgement.

In the above embodiment, the system controlling unit 1402 selects, outof control information inputted from the VBI data multiplexer 73,suitable control information for each VOBU. After storing controlinformation inputted form the VBI data multiplexer 73, the VBI datamultiplexer 73 may detect a point at which the content of the storedcontrol information changes, and control the encoding unit 1404 toposition the detected point in the control information at a start of aVOBU.

A value “10b” of CGMS in DCI may be used to show that “thefirst-generation copy may be generated” although this value of CGMSshows that “condition is not used” in the above embodiment. In theformer case, when receiving a video signal recorded by a user with avideo camera and recording this video signal as a video object onto aDVD-RAM, for instance, the optical disc recorder/player may set one of“copying is permitted without restrictions”, “the first-generation copymay be generated”, and “no more copying is permitted” according to auser selection. The user may set “copying is permitted withoutrestrictions” or “the first-generation copy may be generated” for CGMSwhen the video data (object) on the DVD-RAM is used as a master for thecopying, and may set “no more copying is permitted” when the video dataon the DVD-RAM is not used as a master, for instance.

In the above embodiment, a VOB is described using an M_VOB containingV_PCKs as an example. However, a VOB for the present invention may be anS_VOB (Still Picture_VOB) that contains an S_PCK (Still Picture Pack).In this case, a control pack may be loaded into each VOBU in an S_VOB.

The above embodiment states that values other than “0000b” and “0001b”of four bits (b7-b4) in FIG. 5 are used for the letter box control.However, each of these values may additionally show an aspect ratio of,for instance, 4:3 or 16:9, for an image composed of active image areaand areas out of the active image area, such as the image containingblack parts in FIG. 6.

If a recording stop signal is outputted in step S174 of FIG. 17, the DVDrecorder 75 may stop the recording processing, and be set in an idlestate where a user operation input is awaited.

Although the present invention has been fully described by way ofexamples with reference to accompanying drawings, it is to be noted thatvarious changes and modifications will be apparent to those skilled inthe art. Therefore, unless such changes and modifications depart fromthe scope of the present invention, they should be construed as beingincluded therein.

Industry Applicability

The optical disc recorder/player of the present invention records avideo object unit composed of video object units onto an optical discwhile recording information showing display control and copying controlfor each video object unit having a reproduction time of one second orshorter. When reproducing the video object from the optical disc, theoptical disc recorder/player performs display control and copyingcontrol based on the recorded information. Accordingly, the presentinvention is suited to an optical disc recorder/player that receives avideo signal, records it as a video object onto an optical disc, andreproduces the recorded video object from the optical disc.

What is claimed is:
 1. An optical disc recorder that records a videoobject including a video object unit on an optical disc, the recordercomprising: an extracting arrangement operable to extract a firstcontrol information from a first signal including a first video signal,the first control information relating to at least one of displaycontrol and copy control and extract a second control information from asecond signal including a second video signal, the second controlinformation relating to at least one of display control and copycontrol; an encoding arrangement operable to encode a video signalincluding the first video signal and second video signal to generatevideo data including first video data and second video data; and agenerating arrangement operable to generate the video object unitincluding the video data and one of the first and second controlinformation for fields that correspond to a start of the video objectunit.
 2. The recorder according to claim 1, wherein the generatingarrangement is operable to place the one of the first and second controlinformation at a start of the video object unit.
 3. A recording methodfor recording a video object including a video object unit on an opticaldisc, the recording method comprising: extracting a first controlinformation from a first signal including a first video signal, thefirst control information relating to at least one of display controland copy control and extracting a second control information from asecond signal including a second video signal, the second controlinformation relating to at least one of display control and copycontrol; encoding a video signal including the first video signal andthe second video signal to generate video data including first videodata and second video data; and generating the video object unitincluding the video data and one of the first and second controlinformation for fields that correspond to a start of the video objectunit.
 4. The recording method according to claim 3, wherein thegenerating is operable to place the one of the first and second controlinformation at a start of the video object unit.
 5. An optical discrecorder that records a video object including a video object unit on anoptical disc, the recorder comprising: an extracting arrangementoperable to extract at least three sets of control information from atleast three signals, which include a video signal, the controlinformation relating to at least one of display control and copycontrol; an encoding arrangement operable to encode a signal includingthe at least three signals to generate video data including at leastthree pieces of video data; and a generating arrangement operable togenerate the video object unit including the at least three pieces ofvideo data and one of the at least three sets of control information forfields that correspond to a start of the video object unit.
 6. Therecorder according to claim 5, wherein the generating arrangement isoperable to place the one of the at least three sets of controlinformation at a start of the video object unit.
 7. A recording methodfor recording a video object including a video object unit on an opticaldisc, the recording method comprising: extracting at least three sets ofcontrol information from at least three signals, which include a videosignal, the control information relating to at least one of displaycontrol and copy control; encoding a signal including the at least threesignals to generate video data; and generating the video object unitincluding the least three pieces of video data and one of the at leastthree sets of control information for fields that correspond to a startof the video object unit from the at least three sets of controlinformation.
 8. The recording method according to claim 7, wherein thegenerating is operable to place the one of the at least three sets ofcontrol information at a start of the video object unit.